OpenSceneGraph/CMakeModules/CheckAtomicOps.cmake
2008-06-17 17:43:59 +00:00

102 lines
2.7 KiB
CMake

# Check for availability of atomic operations
# This module defines
# OPENTHREADS_HAVE_ATOMIC_OPS
INCLUDE(CheckCXXSourceRuns)
# Do step by step checking,
CHECK_CXX_SOURCE_RUNS("
#include <cstdlib>
int main()
{
#ifdef __i386__
// Bad, gcc behaves dependent on the compilers -march=... flags.
// Since the osg::Referenced stuff is code distributed in headers, it is
// unclear if we will have this feature available at compile time of the
// headers. So just do not use this feature for 32 bit code.
// May be we can implement around that limitation at some time..
return EXIT_FAILURE;
#else
unsigned value = 0;
void* ptr = &value;
__sync_add_and_fetch(&value, 1);
__sync_synchronize();
__sync_sub_and_fetch(&value, 1);
if (!__sync_bool_compare_and_swap(&value, 0, 1))
return EXIT_FAILURE;
if (!__sync_bool_compare_and_swap(&ptr, ptr, ptr))
return EXIT_FAILURE;
return EXIT_SUCCESS;
#endif
}
" _OPENTHREADS_ATOMIC_USE_GCC_BUILTINS)
CHECK_CXX_SOURCE_RUNS("
#include <cstdlib>
int main(int, const char**)
{
unsigned value = 0;
void* ptr = &value;
__add_and_fetch(&value, 1);
__synchronize(value);
__sub_and_fetch(&value, 1);
if (!__sync_compare_and_swap(&value, 0, 1))
return EXIT_FAILURE;
if (!__sync_compare_and_swap(&ptr, ptr, ptr))
return EXIT_FAILURE;
return EXIT_SUCCESS;
}
" _OPENTHREADS_ATOMIC_USE_MIPOSPRO_BUILTINS)
CHECK_CXX_SOURCE_RUNS("
#include <atomic.h>
#include <cstdlib>
int main(int, const char**)
{
uint_t value = 0;
void* ptr = &value;
atomic_inc_uint_nv(&value);
membar_consumer();
atomic_dec_uint_nv(&value);
if (0 != atomic_cas_uint(&value, 0, 1))
return EXIT_FAILURE;
if (ptr != atomic_cas_ptr(&ptr, ptr, ptr))
return EXIT_FAILURE;
return EXIT_SUCCESS;
}
" _OPENTHREADS_ATOMIC_USE_SUN)
CHECK_CXX_SOURCE_RUNS("
#include <windows.h>
#include <cstdlib>
int main(int, const char**)
{
__declspec(align(32)) volatile long value = 0;
__declspec(align(32)) volatile void* ptr = &value;
InterlockedIncrement(&value);
InterlockedDecrement(&value);
if (0 != InterlockedCompareExchange(&value, 1, 0))
return EXIT_FAILURE;
if (ptr != InterlockedCompareExchangePointer(&ptr, ptr, ptr))
return EXIT_FAILURE;
return EXIT_SUCCESS;
}
" _OPENTHREADS_ATOMIC_USE_WIN32_INTERLOCKED)
IF(NOT _OPENTHREADS_ATOMIC_USE_GCC_BUILTINS AND NOT _OPENTHREADS_ATOMIC_USE_MIPOSPRO_BUILTINS AND NOT _OPENTHREADS_ATOMIC_USE_SUN AND NOT _OPENTHREADS_ATOMIC_USE_WIN32_INTERLOCKED)
SET(_OPENTHREADS_ATOMIC_USE_MUTEX)
ENDIF(NOT _OPENTHREADS_ATOMIC_USE_GCC_BUILTINS AND NOT _OPENTHREADS_ATOMIC_USE_MIPOSPRO_BUILTINS AND NOT _OPENTHREADS_ATOMIC_USE_SUN AND NOT _OPENTHREADS_ATOMIC_USE_WIN32_INTERLOCKED)